基于RNF213介导的FOXO1泛素化修饰探讨五味子乙素调控Treg分化的机制研究OA

Objective:To investigate the effect of Schisandrin B(Sch B)on ring finger protein 213(RNF213)-mediated fork-head box protein O1(FOXO1)ubiquitination and elucidate its molecular mechanism in regulating regulatory T cell(Treg)differ-entiation.Methods:Naïve CD4⁺ T cells were isolated from mouse spleen and lymph nodes,and cell differentiation was induced in the presence of anti-CD3/CD28 antibodies and IL-2 with intervention by different concentrations of Sch B or TGF-β1 except the DMSO group.The proportion of CD4⁺CD25⁺Foxp3⁺ Tregs was detected by flow cytometry.The mRNA and protein expression levels of RNF213 and Foxp3 were measured by RT-qPCR and Western blot,respectively.The K63-linked ubiquitination level of FOXO1 was assessed by co-immunoprecipitation.Lentivirus-mediated gene knockdown and overexpression were employed to veri-fy the functional role of RNF213 in the effects of Sch B.Results:Compared to the DMSO group,Sch B dose-dependently pro-moted the differentiation of naïve CD4⁺ T cells into Tregs,concurrently up-regulated RNF213 expression,enhanced K63-linked ubiquitination of FOXO1,and facilitated FOXO1 nuclear translocation,with statistically significant differences(P<0.01).RNF213 gene knockdown completely abolished the Sch B-induced increases in FOXO1 ubiquitination,nuclear translocation,and Treg dif-ferentiation.Conversely,RNF213 overexpression mimicked the effects of Sch B and exhibited a synergistic effect when combined with Sch B.Conclusion:Sch B can upregulate RNF213 expression,enhance its K63-linked ubiquitination modification of FOXO1,thereby promoting FOXO1 nuclear translocation,and ultimately drive the differentiation of naïve CD4⁺ T cells into Tregs.